The present invention relates to enclosures which provide acoustic damping for printers such as those used in conjunction with personal computing equipment in the home or office, and more particularly to paper guidance systems for such acoustic printer enclosures.
Acoustic printer enclosures are designed to greatly reduce the sound levels emitted by printers to the environment. Such an acoustic enclosure generally consists of a sound absorbing enclosure which substantially completely surrounds the printer, including a shelf for mounting a printer within the enclosure. Typically, such enclosures include a thick transparent hinged cover to allow inspection of the printer and the printed material when the cover is closed and access to the printer and the printer paper when the cover is open. The interior of the acoustic printer enclosure can be lined with a sound absorbing material such as polyurethane foam. There are usually a limited number of openings in the printer enclosure, such as through its side or rear panels, for power and data cables, ventilation, and for printer paper entry and exit.
When printer paper exits, or enters and exits, a paper transport system at the rear of the printer, for example, it is necessary to provide a suitable opening in the rear panel of the acoustic enclosure to allow for paper transport through the panel. In the acoustic enclosure there is usually a gap between the rear panel of the acoustic cover and the paper transport system of the printer. This gap will vary in distance, depending on the brand and model of printer.
However, any significant gap between the paper opening in the acoustic enclosure and the printer allows the paper to sag therebetween, and paper misalignment and misfeed can result. Preferably, some sort of paper guide system is provided in an attempt to minimize the problems associated with this gap. Such guiding systems have included paper support guides of various configurations to restrict paper motion and control the paper path between the printer paper transport system and the paper opening in the acoustic enclosure.
Such paper guiding systems are sometimes formed as an integral portion of a grommet lining the paper opening in the acoustic enclosure. Slots for restricting vertical displacement of paper exiting, or entering and exiting, the paper opening can be formed by horizontal splines extending the width of the grommet. The paper support guides are often just fixed length support tongues mounted along or between the upper and/or lower edges of the grommet, or between the upper or lower grommet edges and a central spline, if such a spline is included. These support tongues can have relatively broad surfaces which support the printed paper from below, or above and below, in the gap between the paper transport system of the printer and the rear panel of the acoustic enclosure. Alternatively, C-shaped channels may be provided as the paper support guides and positioned along the edges of the paper in the gap region to align and support the printer paper. The paper support guides are often laterally adjustable along the grommet to accommodate a variety of paper widths.
The types of paper guiding system described above are not completely satisfactory. Support guides such as the fixed tongues and the edge channels described above work properly when they are of the correct length for the particular gap length between the paper opening and the printer and the correct height for the paper transport system of the printer, but the range of gap length for different printers is so wide that such guides cannot effectively be used with printers of different sizes and configurations, or must be trimmed down to size to fit a particular printer, or must be available in different lengths for different gap lengths. If the guides are trimmed to fit a particular printer, they will not work properly if a printer of a different size or configuration is used in the acoustic enclosure. It is therefore apparent that a universally adjustable paper guide arrangement is highly desirable to allow both standardization of the components of the acoustic printer enclosure and interchangeability of printers.
Consequently, one object of the present invention is to provide a universal guide system for supporting paper transported through an acoustic printer enclosure to or from the paper transport system of a printer housed within the acoustic enclosure.
Another object of the present invention is to standardize the construction of an acoustic printer enclosure with a paper guide system which accommodates a wide range of printer sizes and configurations.
Still another object of the present invention is to improve the reliability of a paper guide system for an acoustic printer enclosure.